To obtain measurements of the geometries and tensions in the wires at various towing speeds for the following gear:
1. "Clupea's" standard 54", 1/2 A.R. flat otterboards, with 7 fm spreading wires and 15 fm sweeps.
2. 60", 1/2 A.R. "V" form otterboards with 7 fm spreading wires and 15 fm sweeps.
3. 66", 1/2 A.R. curved otterboards, with 30 fm twin bridles.
A 22 1/2 ft nylon trawl was used with all these gears.

Chief scientist

John J Foster (Department of Agriculture and Fisheries for Scotland Aberdeen Marine Laboratory)

Cruise report

(0.12 MB)

Ocean/sea areas

General

North Sea

Specific

off Buckie

Measurements

Biology and fisheries

Gear research

Quantity: number of deployments = 2Description: AEI 4 inch recorders were used to record readings from the tension block and spreadmeter

Gear research

Quantity: number of hauls = 25Description: Instrumented hauls made. Measurements of tensions in the warps, the wires fore and aft of the otterboards and at wing ends, headline heights and otterboard spread were obtained for each of the 3 gear conditions at various ship's speed